On Saturday morning Rebecca Rosenberg and I are running together along Rock Creek. I thank her for her gift, a fortnight ago, of a "Mini Zen Gardening Kit" desk toy that I had idly admired on her bookshelf. "I haven't opened it yet," I tell Rebecca, "but just looking at the box next to my computer screen helps me feel a little calmer."

And then I realize that Rebecca gave herself a far more Zen gift: the emptiness where the box used to sit!